When l bought the Lincoln Continental they did not work. l find it unlikely that someone would take them off, so they must still be there. And even more unlikely is that both are completely dead. So is there something i´m missing... a switch or a child lock or something? How can l fix this?

sounds like to me u need a couple of window motors check the fuse first than try all the switch but l am betting on the motors

check the fuses
see your car handbook for location

have you checked the fuse?

have you checked the fuse?

l am assuming the front windows work since u r saying both the rear do not work well no need to check the fuse if the front windows work. Its not uncommon for the rear windows not to get used & they r probably stuck. Try taking the door panel off & get some type of lubricant & spray the tracks & the gear area & start tapping on the motor while holding the switch in the window downward position. do not be afraid to tap fairly hard just make sure u r not near the glass. You may have to do this for a while & u may need to depress the switch lots of times while u r doing it. if this fails & u can verify power to the window motor then u will probably have to replace the motor but most of the time they r just stuck very, very seldom does power window motors actually stop working.

l have a TownCar is the same thing with these lincolns as they get older the first thing that goes out is the window regulators then ur airbags(air Suspension) its very common on these cars l would suggest to try to change the motors but it aint easy you can go to a shop but they will caharge a lot. Try to get them new so that this time they last longer.